The present invention relates to a device for the deflection of a continuously supplied linear structure, such as fibrous thread, yarn or tow, by means of a curved guide tube. Such two- or three-dimensionally curved guide tubes have a wide range of uses, such as in continuously operated synthetic fiber spinning machines wherein they deposit the thread into receiving cans. In such machines the guide tube deflects the vertically delivered thread to a path whose curvature corresponds to that of the side wall of the receiving can. Since the thread is in constant contact with the inner wall of the guide tube in such operations, a high demand is placed upon this inner wall with respect to surface quality and manufacturing precision.
Curved guide tubes consisting of joined individual bending sections, such as are used in pipe line construction, are unsuitable in that edges and projections are necessarily created along the inner edges of the abutting individual segments. On the other hand, continuous curved guide tubes have the disadvantage that the irregular inner surface created after they are bent can no longer be tooled or can only be tooled with considerable expenditure. Such tooling is not possible before bending since the close tooling tolerances necessary are changed during this operation.
A further known practice is to construct a curved guide tube from a series of individual straight tube segments having beveled abutting face surfaces. The faces of these segments are formed as flanges whereby the individual segments are joined. However, these seams form by their nature weak points in the guide tube, especially if the guide tube is set in rotation. In such cases the rotational loads created lead to deformation or even destruction of the device. Additional difficulties arise if the segments are formed so small in their outer dimensions that the screw-type connections ordinarily used with such segments are no longer possible. The non-releasable connections offered as alternatives, i.e., soldering, cementing or welding, are not practical since after such joining there is no possibility of performing the required after-tooling of the internal seam joints. Furthermore, with small outer dimensional segments the resulting joint surfaces are not sufficiently large enough to achieve sufficient connective strength if large rotational loads are experienced.